class: title-slide, center # Tagging cisco: Lessons from the Les Cheneaux Islands ## Todd Hayden, Chris Holbrook .center[<img src="data:image/png;base64,#../images/cisco_drawing.png" width="45%" height="45%"/>] <div class="flex2"> <img src="data:image/png;base64,#../images/MSU.png" width="20%" height="20%"/> <img src="data:image/png;base64,#../images/USGS.png" width="20%" height="20%"/> </div> --- class: top, center # Acknowledgments .left[ - Hammond Bay Biological Station - Michigan Department of Natural Resources - US Fish and Wildlife Service - Real-Time Aquatic Ecosystem Observation Network - Great Lakes Fishery Commission - Great Lakes Acoustic Telemetry Observation System ] .center[ <img src="data:image/png;base64,#../images/icy_night.JPG" width="30%" height="30%" /> ] --- class: top, center # History .left[ - 2017 field tagging trials (Government Bay) - 2018 preliminary project (28 receivers, 25 V9 tags) - 2019-2021 full project (200 tags, 120 receivers) - 2020 winter- capture fish under ice (gill nets) ] <div class="flex2"> <img src="data:image/png;base64,#../images/full_array.png" width="40%" height="40%" /> <img src="data:image/png;base64,#../images/ice_tagging_winter.JPG" width="40%" height="40%" /> </div> --- class: top, center # Capture .left[ - Electrofishing (night) - Peak spawn- approximately November 15 - <4 m water depth during spawn - not available before/after spawning (fish are deep!) - ~ 84% survival (6 months) ] .center[ <img src="data:image/png;base64,#../images/cisco_efish_boat_LesCheneaux_cholbrook_20181108.JPG" width="38%" height="38%"/> ] --- class: top, center # Capture .left[ - Gill net - Very effective during fall- USFWS - Difficult or no recovery, rope burns, lost scales - Tried under ice gill nets, ~20 min soak, ~ 8% survival (6 months) ] .center[ <img src="data:image/png;base64,#../images/inside_ice_shanty_cisco_tagging_winter.JPG" width="18%" height="18%"/> ] --- class: top, center # Post-capture care .left[ - Minimize handling time - Capture <10 fish, transfer fish to waiting "transport boat", tagged on shore - Hold fish in flow-through .red[ROUND] tank (> 1 m) with .red[FLOW] - Surgery immediately after fish "recover" from electrofishing ] .center[ <img src="data:image/png;base64,#../images/cisco_cauldron_bf_tagging.JPG" width="40%" height="40%"/> ] --- class: top, center # Surgery .left[ - Tent, heater to prevent ice formation on fish and us! - V9 tags, fish ~ 400 mm TL, water temp 4-5 C - Record TL, no external tag - TENS electro-immobilisation - <2 min surgery, 2 sutures - Constant water flow over gills - < 1 hour from capture to releases ] <div class="flex2"> <img src="data:image/png;base64,#../images/tent1.JPG" width="30%" height="30%"/> <img src="data:image/png;base64,#../images/tent2.JPG" width="30%" height="30%"/> <img src="data:image/png;base64,#../images/fish_on_surgery_table.JPG" width="30%" height="30%"/> </div> --- class: top, center # Recovery .left[ - Fish released when able to maintain orientation - Dedicated nurse- gently "assist" fish when upside down - Upside down cisco needs care to prevent death! ] <div class="flex2"> <img src="data:image/png;base64,#../images/cisco_nurse_assist.JPG" width="30%" height="30%"/> <img src="data:image/png;base64,#../images/recovery_tank.JPG" width="30%" height="30%"/> </div> --- class: top, center # Tanks and flow .left[ - Round tanks critical, flow through - Rectangular/oval/cattle troughs result in "stuck fish" - How much flow? - Fish should be swimming against current away from side ("endless pool") - Insufficient flow- fish turn upside down - Excessive flow- fish scrape tank sides - We used submersable utility pumps, short hoses, clamps to regulate ] <video width="400" height="300" autoplay loop muted preload> <source src="../images/tagged_cisco_recovery_sm.webm"></source> </video> --- class: top, center # Take-home ideas .left[ - Minimize handling, time in tanks - Round tanks are critical - Sufficient water flow in tanks to promote swimming, flow-through - TENS electro-immobilisation- quick recovery ] .center[<img src="data:image/png;base64,#../images/cisco_on_surgery_table.JPG" width="40%" height="40%"/>]